The Nucleic Acid Core Facility is located in the Department of Gastrointestinal Oncology and Digestive Diseases in a 500 feet/2 laboratory. The Facility was created in the fall of 1996 through a CCSG supplement in Human Cancer Genetics. The NACF is a centralized facility for extraction of high-quality DNA from peripheral blood leukocytes and cell lines by using an Applied Biosystems Model 341 Nucleic Acid Extractor. This allows for the rapid isolation of highly purified, high- molecular-weight DNA. M.D. Anderson Cancer Center has a wealth of patient and family resources for studies of cancer-susceptibility genes. Most DNA isolation techniques used by individual laboratories required significant technical support and take 3 or more days. A centralized automated facility capable of producing PCR-grade DNA overnight from peripheral blood or cell is a major improvement in efficiency. The facility will be expanded to provide PCR-based genetic testing of transgenic animals. Because the high degree of product purity provided by the Model 341 Nucleic Acid Extractor will not be necessary for this testing, a more crude but rapid extraction procedure will be used to isolate DNA from mouse tails. The DNA will be subjected to PCR by using primates specifically designed to detect the transgenes, and animals positive for the transgenes will be identified. A large number of transgenic animal lines from over 20 different laboratories at M.D. Anderson are currently under investigation. Conducting DNA extraction from transgenic animal tails and PCR-based genetic testing in one centralized facility will be more efficient than performing these tasks in individual laboratories, as it will allow automation of each step by the use of Beckman Biomek 2000 robotic arms and multiplex PCR.